Field of the Invention
The present invention relates to a recording apparatus and a recording method.
Description of the Related Art
There is conventionally known a recording apparatus that records images by discharging ink onto a recording medium by driving recording elements, using a recording head having a recording element row where multiple recording elements that generate energy for discharging ink are arrayed. There also is known so-called multi-pass recording in such recording apparatuses, where multiple recording scans are performed as to a unit region to form images.
It is known as of recent in such multi-pass recording to generate recording data using image data expressed as multi-bit information that stipulates how many times ink is to be discharged to each pixel, and multiple mask patterns expressed as multi-bit information that stipulates how many times ink is permitted to be discharged to each pixel, corresponding to multiple scans. For example, Japanese Patent Laid-Open No. 2003-175592 discloses generating recording data using image data and mask patterns each expressed as 2-bit information.
On the other hand, there is commonly known the so-called time-division driving method for a driving methods of multiple recording elements within a recording element row, where the multiple recording elements are divided into multiple driving blocks, and the recording elements belonging to different driving blocks are driven at different timings from each other. This time-division driving method enables the number of recording elements being driven at the same time to be reduced, thereby enabling a recording apparatus to be provided with the size of the driving power source suppressed.
In a case of recording using the above multi-pass recording, there are cases where discharging position deviation of ink occurs among one type of scan and another type of scan in the multiple scans over a unit region, due to various factors. For example, in a case where floating (cockling) of the recording medium occurs in an arrangement where the recording head is reciprocally scanned in the forward direction and backward direction, the ink discharge direction slightly shifts between the forward direction and backward direction, so there is ink discharge position deviation between a region where recording has been performed by a forward direction scan and a region where recording has been performed by a backward direction scan.
In comparison with this, Japanese Patent Laid-Open No. 2013-159017 describes an arrangement to suppress ink discharge position deviation among two types of scans such as forward scan and backward scan described above. In this arrangement recording data is generated where ink is discharged in the same pixel region by these two types of scans, and further the above-described time-division driving is performed so that the landing positions of dots formed by each of the driving blocks in each of the two types of scans differ from each other. Now, in order for the landing positions of dots formed by each of the driving blocks to differ in a case of the recording head being reciprocally scanned in the forward direction and backward direction, the driving order of multiple driving blocks when scanning in the backward direction is described as being different from the reverse order of the driving order of multiple driving blocks when scanning in the forward direction. Also, in order for the landing positions of dots formed by each of the driving blocks to differ in a case of the recording head being scanned only in one direction, the driving order of multiple driving blocks in a certain type of scan is described as being different from the driving order of multiple driving blocks in another certain type of scan. According to Japanese Patent Laid-Open No. 2013-159017, recording can be realized where ink discharge position deviation between two types of scans is suppressed when performing recording using multi-pass recording and time-division driving.
Japanese Patent Laid-Open No. 2013-159017 describes distributing multi-value image data over two types of scans, and thereafter quantizes each image data, so as to generate image data that discharges ink to the same pixel regions in the two types of scans. Thus, recording data that discharges ink to the same pixel regions in the two types of scans is generated, regardless of the concentration of the image data. Accordingly, there is a possibility that recording data that discharges ink to the same pixel regions in the two types of scans will be generated even when processing image data corresponding to a low-concentration image where ink discharge amount is small. As a result, there are cases where ink is applied in a superimposed manner to the same pixel region, even though the dots should be dispersed for low-concentration images from the perspective of uniformity taking uniformity of the image into consideration, yielding an image where graininess is conspicuous.